Slag pocket and method of removing slag



Fh vim, 1923. 1,445,679.

l. H. GRAY.

SLAG POCKET AND METHOD 0F REMOVING SLAG.

FILED MAY 13,-922. 2 SHEETS- sniff 1.

IN VEN TOR.

Juas H @ZAK ATT RNEY.

Feb. 2U, 1923.

. lJ. H. GRAY.

SLAG POCKET AND METHOD 0F REMOVING SLAG.

2 SHEETS-SHEET 2.

FILED MAY 13| 1922.

Il IHlllHllllllll IlllllHl i lllllll i H H I l li llil ll INVENTOR.

llfullenlted lll-fl,

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:reruns n. einen, or new rotin, n. r.

application filed Inlay 1:3,

, 'ift 10.710721, 72mg/ co' j. i it lrno'wn that citiven of the United www anni; o tutes. and r of the city, county,` and State of New lirorlt, have invented certain new and u jful lnil" llrets and Methods of provernentsin @lag )ich the follow: .3

`preheat the gas andair and the products of i combustion at the outgoing end heat the 2c reggenerlators. Below the flues are usually located deep chambers known as slag u poclrfetsvvhich are adapted to catch the suspended particles of pulverized ore, linie cuinulates.

ieee. sei-nu nd. scones.

can be periodically lowered as the slag ac- 'lfhis permits me to usemslagr pockets of rniniiniun depth so that the draft of the furnace not` rnaterialli/ interfered with. lllleans aie`oi.ovicled Whereby` the `accuniulatf i constantly being cooled by expo. .ire to the surroundingatmosphere, so tl at the time the is to be rerncveiil itis` not necessary to lose time to allen/'for such cooling. I

lily invention also contemplates `the use i f slagpoclret h'ai/iisgv a lower marginal seo l ion constructedof material which Will quickly' radiate the heat and to which the slag; Will notreadlljv adhere.

'lflfiose skilled in tne art are aware that open hearth furnaces are often built up of separate VLip-takes for supplying fuel and air and each uutalre is usually built ivith a slag pocket. @ther furnaces adapted to Aburn i liquid fuel are provided with single rip-taires at each end of the furnace throuuh `which the air is introduced. These `up# stoney fluorspar andso `forth carried by the taires act as fines for carryingoff produ-cts gases at the outgoing lend of the furnace.

llt is desirable to Vprevent this dust or slagl frein entering 'the regenerative chambers anch` therefore, the slage pockets are usually formed so that their bottoms are `located a great distance below the port leading; to such regenerative chambers.

`lhe slag gradually accumulates in these deep pockets until it weighs nianjy tons.

At the end `of a furnace campaign., say api prominately three months, it has heretofore been `the practice toopen up the slag` pockets and `Wait for several days to permit them to cool sufliciently so that Workmen could enter and brealr` up the accumulated slapI prior to its manual removal. rlhis is a laborious and expensive operation and necessitates shuttingl `doilvn the furnace for an objectionable length of tune.

Furthermore,when the furance is initially started or put into connnission3` `the slap; pockets at theends ofthe furnace are empty' and constitute lar-ge chambers from which the heat radiates7 `thus cooling the gas or air passing therethrough and interferi1 i' with the draft of the furnace and causingl aslowing up ofthe production. rlhis slowing up or lag may cause as much as a 10% lossV in production.

illy invention contemplates the use of a slage pocket having a movable bottom which of combustion at the outgcningv end of the furnace.` With liquid fuel burning; furnaces it is lonly necessary to provide a single slaufpocket at cach end of the furnaceas will be understood.

` ln the interest of simplicity of illustra i tiornl have shown an open hearth furnace adapted to use liquid fuel and having; one slag pocket at each end of the furnace. `al- `,though it is to be inulerstood that the in" `vention can be practiced in finnaces havi `both .ke/as Vand air iig-takes atcach end i.. the furnace. Y

ln the accompanying drawings, Fig'. l is a longitudinal section through onelend pof an open hearth furnace embodying inv invention. i

Fig. 2 is a transverse section on line 22 of Fig. l; i

Fig. 3 is a detail plan showing means for moving the bottoni of the slagpoclret; y

llig.` is a fragmentary vieiv showinei :i modification;`

Fig, `is a fragmentary `view showing au alternative arrangement for holding the bot-- toni shown in Fig. l;

Figs., 6, 7 and 8 are fragmentary views .illustrating modified details of construe tion. i

Referring lirst to Figs. 'l and 2'. l0 repre` sente a furnace having a hearth Al2 .anda

roof 14 which is connected by a port 16 with a flue 18 which on the incoming end of the furnace tends to convey the air into the t'urnace chamber and on the outgoing; end of the :furnace serves to convey the vproducts ofcombustion to a slag pocliet 2li which is formed with side walls 22 and end walls 24. The end walls 22 are in tact :i continuation of the end walls of the llue 18. A. suitable liquid fuel burner is mounted at 26 and adapted to supply vaporized fuel which will mix with the air introduced through the flue 18. A port 28 is formed in one ot' the walls 22 and communicates with a downwardly inclined port 30 which opens into one ot the regenerative chambers 32.

'lhe lower end of the slag pocket is provided with a marginal section 34, preterably, though not necessarily, made et carbonaceous material such as amorphous carbon formed by packing carbon and compressingl it with tar or pitch as a binder. This section is usually 'formed by blocks which ymay be as large as 28 inches square in section and from 12 to 14 feet long, and the material of which they are made is similar to that used tor the electrodes used in electricare furnaces. rlthis carbonaceous material is an excellent conductor of heat and, therefore, rapidly radiates the heat oit the accumulated slag` to the surrounding atmosphere. It' is also much more slippery than the material of which the walls 22 and 24 of the slag pocket are built, and its nature is such that the accumulated slagv does not tend to adhere thereto as readily as it does to the usual brick walls oit' the slag` pocket.

f The inner surface 36 ot the marginal section 34 may be bevelled as shown in Fig. 1 or it may be a square surface, as shown in Fig. 7. i

Instead of forming` this lower marginal section ot' carbonaceous material, I may provide a water cooled section 23S of box-like lformation as shown in Fig. 8, or I may embed cooling pipes 40 lin the lower end of the. walls of the slag pocket as shown in Fig. 6. The advantage common to the sertion 34, the aclret 38and the cooling` pipes 40, is that the slag accumulated in the lower part of the slagpocket will be cooled as soon as it is deposited on the bottom ot said slag;`

yearbonaceous material I also contemplate the use of graphite blocks which is more more expensive.

The slag pocket 2() is not nearly so deep as slay; pockets liereloorc constructed. As will be seen in Fig. 2, the upper surl'acc 'l2 of the bottom 44 is only a short dislancr` below the port 28 leading to the regenerative chambers.

Means are provided for lowering;- the hotn tom 44 periodically as the slapi accumulincs thereon. is seen in F 2 the bottom 14 is provided with a brick ital-ing 4G and said bottom is supported on a pair olf vertical screws 4S which are shouldered down :il 5l) and seated in bosses 52 'termed on the underside ot the bottom 44. The lioitions` .fili loosely engage the bosses 52 so that when the bottom is moved to its lower position as hereinafter described, the screws can readily he lowered so as to disconnect the bottom therefrom. The screws 4S pass throueh threaded sleeves 5ft termed on .voi'ni gears 56. These sleeves carry a feather ."l so that as the worms 56 are rotated die screws 46 will be moved longitudinally, svi/.l screws being provided with suitable l: y ways 60. Bearings 62 are carried on :i .tired support and rotatably support the worin gears 56. lllorn'is 64 are carried on :i shalt 66 which is ii'iounted in suitable hearings 6H and provided with a squared end TO to which an operating crank or wrench T2 may he zip.- plied. As thus arranged it will he readily seen that by turnim;- the crank "i2 the hot tom 44 can be raised or lowered a t will.

'The slap; pocket side walls are carried hv suitable gggirders 74 which in turn are snpported on columns 76 carried on piers` 7H. lThe columns T6 arc so located that when the bottom 44 is moved to its lowest position as shown in dotted lines in Figi'. l, said hol tom can be moved laterally without interference with said columns.

Located between the columns 2'6 are laterally extending tracks Si() which are urooved to support a plurality ot balli-z S2. 'lhe um derside oiE the bottom LlV-lis provided with curved portions 534 adapted to engage halls 82 when the bottom 44 moved to its lowest position. l

lllhen the furnace, is initially started the bottom fl-4 will he positioned as shown in Fig. 1` and the slag' S will accumulate thereon as shown. The layer olf slag shown is assumed to be only a few inches deep and docs not extend above the top ot the lower section Therefore, the heat ol: this slag' will readily be dissipated into the surrounding' atmosphere. .litter a lirst layer has accu mulated the workmen will give the hand crank 72 a few turns so as to lower the hot tom 44 and permit another layer of slagr to accumulate and cool on the first :formed layer, and this operation will be periodically repeated every two or three days during` the entire run or campaign oit the lniimro which extends approximately over three months loo lllfl lion of the Walls of said slag pocket adaptcd to readily dissipate he heat from the accuinulaed slag.

6. A metallurgical furnace including means for periodically lowering the accumulated slagl to expose itto the cooling effect or" the surrounding` atmosphere.

7. l metallurgical furnace havinga slaga pocket whose Wallsv include ka lower inargjinal secion composed o' niaerial that is 4:':oinparatively slippen'`r and a movable lioj[om arranged to be lowered as the slag' accumulates.

8. A melallurgical furnace having` a slag pocket Whose Walls include a lower comparatively slippery marginal section ol carbonaceous material to which the slag will not adhere the slag' is lowered and a movable lioorn 'for said slagpocket adapted lo be periodically lowered as the slag` accumulates.

9. A metallurgical urnace having a slag pocket provided with a movable bottom, a water cooledv marginal sect-ion adjacent the lower end, of Jche Walls of the slag pocket adapted to prevent the elag from adheringl to said Walls.

10. In combination with the slag pocket of a metallurgical furnace, a movable bot,- loin. means dclachalily engaging raid ino\'ahlc liottoin for periodically loweringY lie liotloin as the slagaccumulates and tracks belov: said slag` pocket adapted lo support said bottom `for lateral movement` in its lowered position.

ll. The method of removing slaanr from the slag' pocket of a furnace which consists in periodicallyv loweringr the bottoni or la slag pocket. during the opcraliion of' the lurnace as the slag accinnulates thereon.

12, The method of removing slaft,r lrom the slagpocket oi a 'furnace which consists in periodically lowering the bottom of the .slag` pocket during the operai-ion of lille ll'urnace as the slagv accumulates thereon and moving` the accumulated mass lal'crallr when llxc luru ace is shut down.

13. The method of reinovinlgr slag; from the slag pocket of an open hearth fornaci` which consists in lowering the sl a f: while the furnace is in operation lo expose it to the cooling` effect oi? the surrouncling armo pliere.

ln wilness whereof, I have hercnnlo signed my naine.

JAMES H. GRAY. 

